The present invention relates to a novel compound 1-cyclohexyl-1,4-dimethyl decahydronaphthalene and a working fluid for traction drive formulated therewith, and more particularly, to 1-cyclohexyl-1,4-dimethyl decahydronaphthalene which is a novel compound suitable as a principal ingredient of working fluids for traction drive or other uses as well as a working fluid for traction drive formulated with this compound.
Generally speaking, a working fluid for traction drive is a fluid used in apparatuses of traction drive, i.e. friction drive apparatuses by rolling contact, such as a continuously variable transmission, and the like. When a fluid for traction drive is used in a high-performance traction drive apparatus, the fluid is required to have a high traction coefficient and stability against heat and oxidation along with inexpensiveness as a matter of course.
In recent years, various types of compounds have been proposed as a fluid for traction drive including various polycyclic naphthenic compounds such as those disclosed in Japanese Patent Publications 338/1971, 339/1971, 35763/1972, 42067/1973, 42068/1973 and 36105/1978 and Japanese Patent Kokai 43108/1980 and 40726/1980.
These compounds, however, have a relatively high viscosity and cannot be free from the problems of a low efficiency of power transmission due to agitation loss and a limitation in the serviceable range of temperature due to the large temperature dependency of the traction coefficient. Moreover, conventional compounds are not satisfactory for the purpose since a fluid for traction drive is sometimes used at a high temperature of up to 120 to 140.degree. C.